Thanks for writing in - sorry to hear about your connection issues!
I see you mention that you’ve restarted Roon Server, have you completely rebooted the Nucleus itself? I’d also reboot your router as well, and see if that allows connection.
From our end, it looks like your Nucleus is having trouble connecting to our servers, which could be pointing to the issue with connecting to upstream services in general. If you have any additional network gear between your Nucleus and router, I’d temporarily bypass it.
Let me know if rebooting your devices helps you establish a connection! Our team isn’t around over the weekends, so if we miss your reply, we’ll be back first thing Monday morning.